Use std::system_category().message(err), which internally dispatches to strerror_r/s, and should handle unknown errors.
See: https://github.com/llvm/llvm-project/blob/4e9e83400a5702059c8a18e2fb6174038875e8a6/libcxx/src/system_error.cpp#L231-L237 for one standard library implementation.
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Use std::system_category().message(err), which internally dispatches to
strerror_r/s, and should handle unknown errors.
See: https://github.com/llvm/llvm-project/blob/4e9e83400a5702059c8a18e2fb6174038875e8a6/libcxx/src/system_error.cpp#L231
6 | @@ -7,9 +7,8 @@ 7 | 8 | #include <string> 9 | 10 | -/** Return system error string from errno value. Use this instead of 11 | - * std::strerror, which is not thread-safe. For network errors use 12 | - * NetworkErrorString from sock.h instead. 13 | +/** Return system error string from errno value. For network errors 14 | + * use NetworkErrorString from sock.h instead.
/// Return system error string from errno value. For network errors
/// use NetworkErrorString from sock.h instead.
nit: The different indent looks a bit ugly? Could use a fixed-size doxygen comment?
Sure, changed.